title: Pelger-huet anomaly and a mild skeletal phenotype secondary to mutations in LBR.
abstract: The Lamin B receptor (LBR) gene has been described to encode a bifunctional protein. Mutations in the LBR gene can affect neutrophil segmentation and sterol reductase activity and have been associated with two different recognized clinical conditions, Pelger-Huet anomaly (PHA) and Greenberg skeletal dysplasia. PHA is a benign autosomal co-dominant laminopathy resulting in bilobed neutrophil nuclei in heterozygotes, and unsegmented (ovoid) neutrophil nuclei in homozygotes. Some putative PHA homozygotes have been reported with minor skeletal malformations. Greenberg skeletal dysplasia is a severe autosomal recessive, perinatal lethal dwarfing disorder in which heterozygous carriers are usually without clinical manifestations. We here report a girl who has bilobed neutrophil nuclei and a mild skeletal dysplasia. Mutation analysis showed two novel mutations in the LBR gene: c.651_653 delinsTGATGAGAAA (p.Ile218Aspfs*19) and c.1757G > A (p.Arg586His). These mutations were found to be in trans, and, thus, she is a compound heterozygote. Sterol analysis found trace amounts of cholesta-8,14-dien-3beta-ol, which is normally undetected in healthy individuals. This and previously reported cases suggest that mutations in LBR can result in a continuum of phenotypic manifestations.
authors.affiliation: Department of Pediatrics, University of Wisconsin-Madison, Madison, WI 53705, USA.
authors.forename: Lior
authors.initials: L
authors.lastname: Borovik
authors.forename: Peggy
authors.initials: P
authors.lastname: Modaff
authors.forename: Hans R
authors.initials: HR
authors.lastname: Waterham
authors.forename: Anthony D
authors.initials: AD
authors.lastname: Krentz
authors.forename: Richard M
authors.initials: RM
authors.lastname: Pauli
mesh_terms: D002648:Child; D005260:Female; D006579:Heterozygote; D006801:Humans; D009154:Mutation / Q000235:genetics*; D009504:Neutrophils / Q000473:pathology*; D010009:Osteochondrodysplasias / Q000209:etiology* / Q000473:pathology; D010381:Pelger-Huet Anomaly / Q000209:etiology* / Q000473:pathology; D010641:Phenotype; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics*; D000097682:Lamin B Receptor
chemical_list: D018160:Receptors, Cytoplasmic and Nuclear; D000097682:Lamin B Receptor
keywords: Greenberg skeletal dysplasia; cholesterol synthesis; dumbbell nuclei; homozygotes/compound heterozygotes; skeletal anomalies; sterol reductase